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-rwxr-xr-xbin/diff-highlight218
1 files changed, 0 insertions, 218 deletions
diff --git a/bin/diff-highlight b/bin/diff-highlight
deleted file mode 100755
index ffefc31..0000000
--- a/bin/diff-highlight
+++ /dev/null
@@ -1,218 +0,0 @@
-#!/usr/bin/perl
-
-use 5.008;
-use warnings FATAL => 'all';
-use strict;
-
-# Highlight by reversing foreground and background. You could do
-# other things like bold or underline if you prefer.
-my @OLD_HIGHLIGHT = (
- color_config('color.diff-highlight.oldnormal'),
- color_config('color.diff-highlight.oldhighlight', "\x1b[7m"),
- color_config('color.diff-highlight.oldreset', "\x1b[27m")
-);
-my @NEW_HIGHLIGHT = (
- color_config('color.diff-highlight.newnormal', $OLD_HIGHLIGHT[0]),
- color_config('color.diff-highlight.newhighlight', $OLD_HIGHLIGHT[1]),
- color_config('color.diff-highlight.newreset', $OLD_HIGHLIGHT[2])
-);
-
-my $RESET = "\x1b[m";
-my $COLOR = qr/\x1b\[[0-9;]*m/;
-my $BORING = qr/$COLOR|\s/;
-
-my @removed;
-my @added;
-my $in_hunk;
-
-# Some scripts may not realize that SIGPIPE is being ignored when launching the
-# pager--for instance scripts written in Python.
-$SIG{PIPE} = 'DEFAULT';
-
-while (<>) {
- if (!$in_hunk) {
- print;
- $in_hunk = /^$COLOR*\@/;
- }
- elsif (/^$COLOR*-/) {
- push @removed, $_;
- }
- elsif (/^$COLOR*\+/) {
- push @added, $_;
- }
- else {
- show_hunk(\@removed, \@added);
- @removed = ();
- @added = ();
-
- print;
- $in_hunk = /^$COLOR*[\@ ]/;
- }
-
- # Most of the time there is enough output to keep things streaming,
- # but for something like "git log -Sfoo", you can get one early
- # commit and then many seconds of nothing. We want to show
- # that one commit as soon as possible.
- #
- # Since we can receive arbitrary input, there's no optimal
- # place to flush. Flushing on a blank line is a heuristic that
- # happens to match git-log output.
- if (!length) {
- local $| = 1;
- }
-}
-
-# Flush any queued hunk (this can happen when there is no trailing context in
-# the final diff of the input).
-show_hunk(\@removed, \@added);
-
-exit 0;
-
-# Ideally we would feed the default as a human-readable color to
-# git-config as the fallback value. But diff-highlight does
-# not otherwise depend on git at all, and there are reports
-# of it being used in other settings. Let's handle our own
-# fallback, which means we will work even if git can't be run.
-sub color_config {
- my ($key, $default) = @_;
- my $s = `git config --get-color $key 2>/dev/null`;
- return length($s) ? $s : $default;
-}
-
-sub show_hunk {
- my ($a, $b) = @_;
-
- # If one side is empty, then there is nothing to compare or highlight.
- if (!@$a || !@$b) {
- print @$a, @$b;
- return;
- }
-
- # If we have mismatched numbers of lines on each side, we could try to
- # be clever and match up similar lines. But for now we are simple and
- # stupid, and only handle multi-line hunks that remove and add the same
- # number of lines.
- if (@$a != @$b) {
- print @$a, @$b;
- return;
- }
-
- my @queue;
- for (my $i = 0; $i < @$a; $i++) {
- my ($rm, $add) = highlight_pair($a->[$i], $b->[$i]);
- print $rm;
- push @queue, $add;
- }
- print @queue;
-}
-
-sub highlight_pair {
- my @a = split_line(shift);
- my @b = split_line(shift);
-
- # Find common prefix, taking care to skip any ansi
- # color codes.
- my $seen_plusminus;
- my ($pa, $pb) = (0, 0);
- while ($pa < @a && $pb < @b) {
- if ($a[$pa] =~ /$COLOR/) {
- $pa++;
- }
- elsif ($b[$pb] =~ /$COLOR/) {
- $pb++;
- }
- elsif ($a[$pa] eq $b[$pb]) {
- $pa++;
- $pb++;
- }
- elsif (!$seen_plusminus && $a[$pa] eq '-' && $b[$pb] eq '+') {
- $seen_plusminus = 1;
- $pa++;
- $pb++;
- }
- else {
- last;
- }
- }
-
- # Find common suffix, ignoring colors.
- my ($sa, $sb) = ($#a, $#b);
- while ($sa >= $pa && $sb >= $pb) {
- if ($a[$sa] =~ /$COLOR/) {
- $sa--;
- }
- elsif ($b[$sb] =~ /$COLOR/) {
- $sb--;
- }
- elsif ($a[$sa] eq $b[$sb]) {
- $sa--;
- $sb--;
- }
- else {
- last;
- }
- }
-
- if (is_pair_interesting(\@a, $pa, $sa, \@b, $pb, $sb)) {
- return highlight_line(\@a, $pa, $sa, \@OLD_HIGHLIGHT),
- highlight_line(\@b, $pb, $sb, \@NEW_HIGHLIGHT);
- }
- else {
- return join('', @a),
- join('', @b);
- }
-}
-
-sub split_line {
- local $_ = shift;
- return utf8::decode($_) ?
- map { utf8::encode($_); $_ }
- map { /$COLOR/ ? $_ : (split //) }
- split /($COLOR+)/ :
- map { /$COLOR/ ? $_ : (split //) }
- split /($COLOR+)/;
-}
-
-sub highlight_line {
- my ($line, $prefix, $suffix, $theme) = @_;
-
- my $start = join('', @{$line}[0..($prefix-1)]);
- my $mid = join('', @{$line}[$prefix..$suffix]);
- my $end = join('', @{$line}[($suffix+1)..$#$line]);
-
- # If we have a "normal" color specified, then take over the whole line.
- # Otherwise, we try to just manipulate the highlighted bits.
- if (defined $theme->[0]) {
- s/$COLOR//g for ($start, $mid, $end);
- chomp $end;
- return join('',
- $theme->[0], $start, $RESET,
- $theme->[1], $mid, $RESET,
- $theme->[0], $end, $RESET,
- "\n"
- );
- } else {
- return join('',
- $start,
- $theme->[1], $mid, $theme->[2],
- $end
- );
- }
-}
-
-# Pairs are interesting to highlight only if we are going to end up
-# highlighting a subset (i.e., not the whole line). Otherwise, the highlighting
-# is just useless noise. We can detect this by finding either a matching prefix
-# or suffix (disregarding boring bits like whitespace and colorization).
-sub is_pair_interesting {
- my ($a, $pa, $sa, $b, $pb, $sb) = @_;
- my $prefix_a = join('', @$a[0..($pa-1)]);
- my $prefix_b = join('', @$b[0..($pb-1)]);
- my $suffix_a = join('', @$a[($sa+1)..$#$a]);
- my $suffix_b = join('', @$b[($sb+1)..$#$b]);
-
- return $prefix_a !~ /^$COLOR*-$BORING*$/ ||
- $prefix_b !~ /^$COLOR*\+$BORING*$/ ||
- $suffix_a !~ /^$BORING*$/ ||
- $suffix_b !~ /^$BORING*$/;
-}